Fabrication of core/shell capsules of different geometries and treatment thereafter

Abstract

Multi-shelled capsules are made by co-extruding a first liquid flavorant composition and a first shell-forming polymeric material to form droplets which are hardened to form an inner shell containing a first liquid flavorant composition, and then coated with a second shell-forming polymeric material which is hardened to form an outer shell. The result is a capsule where the inner surface of the outer shell is separate and/or separable from the outer surface of the inner shell to define a space, wherein a second liquid flavorant composition may be located.

What is claimed is: 
     
       1. A method for encapsulating a liquid flavorant composition in a multi-shelled capsule, comprising:
 (a) co-extruding a first liquid flavorant composition and a first shell-forming polymeric material to form a core-shell droplet; 
 (b) hardening the first shell-forming polymeric material of the droplet to form an inner shell around an inner core, the inner core comprising the first liquid flavorant composition; 
 (c) coating the inner shell with a coating layer comprising a second shell-forming polymeric material; and 
 (d) hardening the second shell-forming polymeric material by contacting the second shell-forming polymer with polyvalent metal ions present in or on the inner shell, to form an outer shell of the multi-shelled capsule, 
 wherein the co-extruding step comprises using a co-extruder comprising an inner nozzle having a diameter of between about 0.5 mm and 2 mm, and an outer nozzle having a diameter of between about 1.5 mm and 3 mm, and 
 wherein the first liquid flavorant composition is fed to the inner nozzle at between about 40 mbar and 80 mbar, and the first shell-forming polymeric material is fed to the outer nozzle at between about 100 mbar and 130 mbar. 
 
     
     
       2. The method of  claim 1 , wherein an inner surface of the outer shell is separated from an outer surface of the inner shell. 
     
     
       3. The method of  claim 2 ,
 further comprising forming a second liquid region at least partially between the outer surface of the inner shell and the inner surface of the outer shell. 
 
     
     
       4. The method of  claim 1 , wherein the multi-shelled capsule has a burst strength measured using a Shimadzu EZ-Graph with a compression speed of 100 mm/min of between about 6 and 11 N. 
     
     
       5. The method of  claim 1 , wherein said first liquid flavorant composition comprises a first flavorant selected from the group consisting of menthol, mint, chocolate, licorice, citrus and other fruit flavors, gamma octalactone, vanillin, ethyl vanillin, cinnamon, methyl salicylate, linalool, bergamot oil, geranium oil, lemon oil, ginger oil, tobacco extract, phenylacetic acid, solanone, megastigmatrienone, 2-heptanone, benzylalcohol, cis-3-hexenyl acetate, valeric acid, valeric aldehyde, and mixtures thereof. 
     
     
       6. The method of  claim 1 , wherein the multi-shelled capsule is substantially spherical or ovoid. 
     
     
       7. The method of  claim 1 , wherein said hardening the second shell-forming polymeric material comprises drying in a tumbling dryer. 
     
     
       8. A method for encapsulating a liquid flavorant composition in a multi-shelled capsule, comprising:
 (a) co-extruding a first liquid flavorant composition and a first shell-forming polymeric material to form a core-shell droplet; 
 (b) hardening the first shell-forming polymeric material of the droplet to form an inner shell around an inner core, the inner core comprising the first liquid flavorant composition; 
 (c) coating the inner shell with a coating layer comprising a second shell-forming polymeric material; and 
 (d) hardening the second shell-forming polymeric material by contacting the second shell-forming polymer with polyvalent metal ions present in or on the inner shell, to form an outer shell of the multi-shelled capsule, 
 wherein an inner surface of the outer shell is separated from an outer surface of the inner shell, 
 the method further comprising forming a second liquid region at least partially between the outer surface of the inner shell and the inner surface of the outer shell by one of the following: 
 (a′) coating the inner shell with a gel comprising one or more components that are substantially insoluble in the second shell-forming polymeric material, whereby before or upon hardening of the second shell-forming polymeric material the second liquid region is formed and comprises the one or more components that are substantially insoluble; or 
 (b′) before the second shell-forming polymeric material is completely hardened, contacting either the coated inner shell or the multi-shelled capsule with a second liquid flavorant composition for a time and under conditions sufficient for at least a portion of said second liquid flavorant composition to move through said outer shell or said coating layer to form said liquid region, followed by hardening of the second shell-forming polymeric material. 
 
     
     
       9. The method of  claim 8 , wherein said first shell-forming polymeric material comprises a cross-linkable polysaccharide, a hardenable protein, or a hardenable wax. 
     
     
       10. The method of  claim 9 , wherein said cross-linkable polysaccharide is selected from the group consisting of alginates, pectins, carrageenans, chitosans, dextrans, and combinations or mixtures thereof. 
     
     
       11. The method of  claim 10 , wherein the first and second shell-forming polymeric materials each comprise a cross-linkable alginate. 
     
     
       12. The method of  claim 8 , wherein the multi-shelled capsule has a burst strength measured using a Shimadzu EZ-Graph with a compression speed of 100 mm/min of between about 6 and 11 N. 
     
     
       13. The method of  claim 8 , wherein said first liquid flavorant composition comprises a first flavorant selected from the group consisting of menthol, mint, chocolate, licorice, citrus and other fruit flavors, gamma octalactone, vanillin, ethyl vanillin, cinnamon, methyl salicylate, linalool, bergamot oil, geranium oil, lemon oil, ginger oil, tobacco extract, phenylacetic acid, solanone, megastigmatrienone, 2-heptanone, benzylalcohol, cis-3-hexenyl acetate, valeric acid, valeric aldehyde, and mixtures thereof. 
     
     
       14. The method of  claim 8 , wherein the multi-shelled capsule is substantially spherical or ovoid. 
     
     
       15. The method of  claim 8 , wherein said hardening the second shell-forming polymeric material comprises drying in a tumbling dryer. 
     
     
       16. A method for encapsulating a liquid flavorant composition in a multi-shelled capsule, comprising:
 (a) co-extruding a first liquid flavorant composition and a first shell-forming polymeric material to form a core-shell droplet; 
 (b) hardening the first shell-forming polymeric material of the droplet to form an inner shell around an inner core, the inner core comprising the first liquid flavorant composition; 
 (c) coating the inner shell with a coating layer comprising a second shell-forming polymeric material; and 
 (d) hardening the second shell-forming polymeric material by contacting the second shell-forming polymer with polyvalent metal ions present in or on the inner shell, to form an outer shell of the multi-shelled capsule, 
 wherein said co-extruding step comprises using a co-extruder having an electromagnetic shaker operating at a frequency of between about 20 and 200 Hz and an amplitude of between about 100 and 2000 mV. 
 
     
     
       17. The method of  claim 16 , wherein the multi-shelled capsule has a burst strength measured using a Shimadzu EZ-Graph with a compression speed of 100 mm/min of between about 6 and 11 N. 
     
     
       18. The method of  claim 16 , wherein said first liquid flavorant composition comprises a first flavorant selected from the group consisting of menthol, mint, chocolate, licorice, citrus and other fruit flavors, gamma octalactone, vanillin, ethyl vanillin, cinnamon, methyl salicylate, linalool, bergamot oil, geranium oil, lemon oil, ginger oil, tobacco extract, phenylacetic acid, solanone, megastigmatrienone, 2-heptanone, benzylalcohol, cis-3-hexenyl acetate, valeric acid, valeric aldehyde, and mixtures thereof. 
     
     
       19. The method of  claim 16 , wherein the multi-shelled capsule is substantially spherical or ovoid. 
     
     
       20. The method of  claim 16 , wherein said first shell-forming polymeric material comprises a cross-linkable polysaccharide, a hardenable protein, or a hardenable wax. 
     
     
       21. The method of  claim 20 , wherein said cross-linkable polysaccharide is selected from the group consisting of alginates, pectins, carrageenans, chitosans, dextrans, and combinations or mixtures thereof. 
     
     
       22. The method of  claim 21 , wherein the first and second shell-forming polymeric materials each comprise a cross-linkable alginate. 
     
     
       23. The method of  claim 16 , wherein said hardening the second shell-forming polymeric material comprises drying in a tumbling dryer.